Transfer case
 

I have 2000 rt 4x4 durango. It has the manual. The shift can move with no force to it in any gear. It will not ingauge to and 4x4 mode. Can anyone help as to what could be wrong. Thank you

Check the linkage.

+1, sounds like the rubber bushings in the linkage disintegrated, they tend to do that when they get old, hopefully you didnt lose the linkage (uncommon, but possible)

The linkage is still there. If the rubber bushing are bad would I still be able to crawl under the truck and still be able to manually shift it to 4x4?

Have someone else move the lever, while you watch and see what the linkage is doing.

Ya I did that. It moves with the lever it just won't shift in to any of the gears

There should be clunking going on in the t-case when you move the lever. Is that happening? If you look at the tear down of the t-case in the FSM, you can see it's just one rotating part that shifts two forks (one hi/lo and the other 2/4). If the main exterior lever is moving to all the positions and yet it's still not shifting, it's kinda not possible to do that unless something is broken inside.
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Thats what I was think because its all loose

Does any one know what transfer case it is

Read the round tag in the back.
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